# Samarium-153 lexidronam

Source: https://nuclide.cc/drugs/samarium-153-lexidronam/  
Nuclide record `samarium-153-lexidronam` (Agent). Data CC BY-NC 4.0, attribute "Data from Nuclide (nuclide.cc)"; commercial use needs a licence.

## TL;DR

Quadramet (samarium-153 lexidronam) is a radioactive bone-seeking injection that lodges in bone metastases and irradiates them from inside, approved in 1997 to relieve pain from prostate, breast and other cancers spread to bone. Most patients get relief within one to two weeks, but marrow suppression follows at three to five weeks, and radium-223 and PSMA radioligands have largely replaced it.

## Summary

Samarium-153 lexidronam was approved by the FDA in March 1997 and authorised in the EU in February 1998 for relief of pain in patients with confirmed osteoblastic metastatic bone lesions that take up technetium-labelled bisphosphonate on bone scan, on placebo-controlled trials in which most patients had pain relief within one to two weeks lasting for months. It and strontium-89 (Metastron) were the bone-pain radiopharmaceuticals of the 1990s; radium-223 (Xofigo), which extends survival in prostate cancer, and PSMA radioligands have since taken most of their role. A single intravenous dose is given; transient marrow suppression, with nadir at three to five weeks, is the main toxicity, and a pain flare can occur early. Distributed by Lantheus in the US and Curium in Europe.

## Fields

- Kind: Agent
- Status: approved
- Last checked: 2026-09-10
- Also known as: 153Sm-EDTMP; Samarium Sm 153 lexidronam pentasodium
- Tags: ema-list; supportive
- Brand: Quadramet
- Modality: Bone-seeking therapeutic radiopharmaceutical (beta emitter)
- Mechanism: Samarium-153 chelated to the tetraphosphonate EDTMP concentrates in areas of high bone turnover around osteoblastic metastases; beta emission (1.9 day half-life) irradiates the metastases and relieves pain, with gamma emission allowing imaging.
- Approvals: US 1997: Relief of pain in patients with confirmed osteoblastic metastatic bone lesions that enhance on radionuclide bone scan; EU 1998: Relief of bone pain from multiple painful osteoblastic skeletal metastases (Quadramet)

## Sources

- Wikipedia: https://en.wikipedia.org/wiki/Samarium_(153Sm)_lexidronam
- EPAR (EMA): https://www.ema.europa.eu/en/medicines/human/EPAR/quadramet
- US label (DailyMed): https://dailymed.nlm.nih.gov/dailymed/search.cfm?labeltype=all&query=samarium

## Connected records

- drugs: [Radium-223 dichloride](https://nuclide.cc/drugs/radium-223/), [Strontium-89 chloride](https://nuclide.cc/drugs/sr-89-chloride/)
- isotopes: [Radium-223](https://nuclide.cc/isotopes/ra-223/), [Samarium-153](https://nuclide.cc/isotopes/sm-153/), [Strontium-89](https://nuclide.cc/isotopes/sr-89/)
- indications: [Bone pain palliation from osteoblastic metastases](https://nuclide.cc/indications/bone-pain-palliation/), [Prostate cancer](https://nuclide.cc/indications/prostate/)
- technologies: [Radioligand therapy (beta emitters)](https://nuclide.cc/technologies/radioligand-therapy/)
- companies: [Curium](https://nuclide.cc/companies/curium/), [Lantheus](https://nuclide.cc/companies/lantheus/)
- fronts: [Bone-targeted radiopharmaceuticals](https://nuclide.cc/fronts/f-bone-targeted/)
- targets: [Bone mineral (hydroxyapatite)](https://nuclide.cc/targets/bone-hydroxyapatite/)

---
JSON: https://nuclide.cc/api/v1/entities/samarium-153-lexidronam.json